A Virgo high-resolution Halpha kinematical survey : II. The Atlas

Abstract

A catalog of ionized gas velocity fields for a sample of 30 spiral and irregular galaxies of the Virgo cluster has been obtained by using three-dimensional optical data. The aim of this survey is to study the influence of high density environments on the gaseous kinematics of local cluster galaxies. Observations of the Halpha line by means of Fabry-Perot interferometry have been performed at the Canada-France-Hawaii, ESO 3.6m, Observatoire de Haute-Provence 1.93m and Observatoire du mont Megantic telescopes at angular and spectral samplings from 0.4" to 1.6" and 7 to 16 km/s. A recently developed, automatic and adaptive spatial binning technique is used to reach a nearly constant signal-to-noise ratio (S/N) over the whole field-of-view, allowing to keep a high spatial resolution in high S/N regions and extend the detection of signal in low S/N regions. This paper is part of a series and presents the integrated emission-line and velocity maps of the galaxies. Both Halpha morphologies and kinematics exhibit signs of perturbations in the form of e.g. external filaments, inner and nuclear spiral- and ring-like structures, inner kinematical twists, kinematical decoupling of a nuclear spiral, streaming motions along spiral arms and misalignment between kinematical and photometric orientation axes.